Near infrared light consists of light just beyond visible red light (wavelengths greater than 780nm). Contrary to popular thought, near infrared photography does not allow the recording of thermal radiation (heat). Far-infrared thermal imaging requires more specialized equipment. Infrared images exhibit a few distinct effects that give them an exotic, antique look. Plant life looks completely white because it reflects almost all infrared light (because of this effect, infrared photography is commonly used in aerial photography to analyze crop yields, pest control, etc.) The sky is a stark black because no infrared light is scattered. Human skin looks pale and ghostly. Dark sunglasses all but disappear in infrared because they don't block any infrared light, and it's said that you can capture the near infrared emissions of a common iron.

Infrared photography has been around for at least 70 years, but until recently has not been easily accessible to those not versed in traditional photographic processes. Since the charge-coupled devices (CCDs) used in digital cameras and camcorders are sensitive to near-infrared light, they can be used to capture infrared photos. With a filter that blocks out all visible light (also frequently called a "cold mirror" filter), most modern digital cameras and camcorders can capture photographs in infrared. In addition, they have LCD screens, which can be used to preview the resulting image in real-time, a tool unavailable in traditional photography without using filters that allow some visible (red) light through.

INTRODUCTION

Near infrared light consists of light just beyond visible red light (wavelengths greater than 780nm). Contrary to popular thought, near infrared photography does not allow the recording of thermal radiation (heat). Far-infrared thermal imaging requires more specialized equipment. Infrared images exhibit a few distinct effects that give them an exotic, antique look. Plant life looks completely white because it reflects almost all infrared light (because of this effect, infrared photography is commonly used in aerial photography to analyze crop yields, pest control, etc.) The sky is a stark black because no infrared light is scattered. Human skin looks pale and ghostly. Dark sunglasses all but disappear in infrared because they don't block any infrared light, and it's said that you can capture the near infrared emissions of a common iron

Near-infrared (1000 - 3000 nm) spectrometry, which employs an external light source for determination of chemical composition, has been previously utilized for industrial determination of the fat content of commercial meat products, for in vivo determination of body fat, and in our laboratories for determination of lipoprotein composition in carotid artery atherosclerotic plaques. Near-infrared (IR) spectrometry has been used industrially for several years to determine saturation of unsaturated fatty acid esters (1). Near-IR spectrometry uses an tunable light source external to the experimental subject to determine its chemical composition. Industrial utilization of near-IR will allow for the in vivo measurement of the tissue-specific rate of oxygen utilization as an indirect estimate of energy expenditure. However, assessment of regional oxygen consumption by these methods is complex, requiring a high level of surgical skill for implantation of indwelling catheters to isolate the organ under study